Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and external-fetch profile is covered; the description adds substantive context on top: it returns a 0-100 score, per-check notes and an evidence hash, it is free, and it is explicitly not a security certification. What it does not disclose is timing or rate-limit behaviour for a live multi-endpoint crawl, which is the main remaining unknown.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, no filler, and the front-loaded clause states purpose before the check list. The return-value and disclaimer clauses each carry distinct information, so every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description correctly compensates by naming the return shape (score, per-check notes, evidence hash), and the sole parameter is fully documented in the schema. It stops short of saying what a caller should expect when checks fail or time out, which matters for a live open-world audit, but nothing essential to invoking it is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the single url parameter already documents 'Domain or https URL, e.g. example.com'. The description adds nothing about accepted formats, redirect handling or whether http:// is tolerated, so this is the standard baseline-3 case where the schema does all the work.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb and resource ('Audit how ready a public website is for AI agents') and then enumerates exactly which signals are inspected (A2A agent card, llms.txt, MCP discovery, OpenAPI, robots.txt, agents.json, skills, x402, sitemap). That enumeration also makes it self-evidently the aggregate counterpart to the individual bursia_check_* siblings, so an agent can distinguish it without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied rather than stated: it is clearly for auditing a public site, and the individual check tools in the sibling list are the obvious alternative, but the description never says 'use this for a one-shot overview, use bursia_check_llms_txt for a single check' or any equivalent. The only explicit boundary is a scope disclaimer ('not a security certification'), which is useful but is not routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.